While my engine is apart awaiting the return of my extrude/honed intake manifold (and next month my supercharger) I was wondering about beefing up my alternator or replacing it with a bigger one.

I wanted an alternator that would have more of an amperage reserve when my large stereo puts a load on it...

Recommendations?

 

I don't know what your, "large stereo," is gonna be like, but isn't Optima yellow top battery and larger capacitor the way to go?

 

Isn't the alternator a charging unit? I though that power came from the battery even while charging. True or no?

 

If you are running a high drain system such as a heavy duty stereo set up with big amps and sub, you will easily overpower the altenator in th S2000. The Optima batteries and 1 Farad Capacitors are a small fix to a system that spikes above the alt's capability on occasions. Their purpose is more to allow the amplifiers to run at full output when being really pushed, rather than to fix an underpowered electrical system. I have been to several high end stereo shops looking for a system for my S2k and they all mention that the stooks tiny 55amp altenator will easily be overpowered by a strong amplifier running good subs. Apparently alot of people running high end systems also run 150+ amp altenators, as well as caps. They have all advised me to stick to moderate powered systems and one small efficient subwoofer with a 1 farad cap sliced in near the amp, unless I plan on upgrading the altenator as well.

By the way, replacing an alt. with a high power one can be extremely expensive, I'm told. I was afraid to ask how much.

 

Voltage coming from the battery is 12V. Most cars with modern electronics lets the alternator bump the overall voltage upto 14.4 V while maintaing a charging in the battery.

But If the alternator is too small and the power usage (stereo, headlight etc.) is too high the battery will get drained without ever getting charged.

Getting a alternator upgrade isn't required with minor stereo upgrade as most stock alternators produce more than enough power once the car gets moving.

Bigger alternator IMO will just be more parasitic. And besides this is a small convertible with 400lb load limit. I doubt you will want to add anyting more that a sub, a component set and an amp to power them.

 

[QUOTE]Originally posted by Z3toS2K:
[B]If you are running a high drain system such as a heavy duty stereo set up with big amps and sub, you will easily overpower the altenator in th S2000. The Optima batteries and 1 Farad Capacitors are a small fix to a system that spikes above the alt's capability on occasions.

 

Think that honed intake is gonna make up for the power loss created by a larger altenator and the extra weight of your stereo set up?

One step up and two steps back.

 

Don't have my shop manual yet, but most places I've seen list output at 105 amps, which is indeed big for a Honda. http://english.honda.ca/models/s2000_features.asp
How come the Canadians get more detailed specs on their page?

Try measuring the average drain of your current (no pun intended) setup at the alternator (engine revved a little, fan, stereo and whatever else on) to see how things are now. Then subtract from 105 to see what you've got left "in reserve". One would be hard pressed to fit enough speakers in our cars (at least without drastic modification or terminal loss of trunk space) to draw more than a few hundred watts RMS, which is only 15-30 amps. A battery upgrade is definitely a good idea, if for no other reason than the increased engine-off listening time. The stock 36A-H is pretty wimpy.
Once all your system is installed, you can install a voltmeter to be sure it's not working at a power defecit. It would also tell you if the bass hits are seriously dropping your system voltage, which would indicate a need for more capacitance.
With a properly installed and grounded system you alt should be fine, but I would avoid blasting Bass Mekanik while simultaneously raising the top and turning the wheel and shining the brights with the A/C on full blast while pumping up a tire with a 12v air compressor running off the cigarette lighter plug.

May all our battery lights stay off,
Jason

 

First of all, I did not ask for opinions on my stereo or my engine mods... I asked only for alternator change advice. I changed my alternator in my other car with a 160 amp one and it worked beatufully.

Stiffening capacitors merely level out current draw and do not supply more amperage. Battery improvements (I have had multiple Optima batteries) merely lower internal resistance which gives faster current response. Optima batteries can also be run down more times and completely recharged better than traditional lead acid batteries... But a better battery will still die if the alternator is not providing enough charging current while providing current to other car/engine accessories.

And Bieg, it's no wonder people cannot stand you... An alternator will provide a horsepower load on the engine when there is a current load. If I want maximun horsepower from all of my mods (intake hone and all) then I can merely not use my stereo and the alternator will provide "normal" horsepower drain from the engine.

How about reading people's posts and commenting to yourself and just not typing them?

 

[QUOTE]An alternator will provide a horsepower load on